STRENGTHENING IRON FISCHER-TROPSCH CATALYST BY CO-FEEDING IRON NITRATE AND PRECIPITATING AGENT OR SEPARATELY PRECIPITATING FROM FERROUS NITRATE AND FERRIC NITRATE SOLUTIONS

1 . A method of producing a catalyst precursor comprising iron phases, the method comprising:

(a) co-feeding a ferrous nitrate solution and a precipitation agent into a ferric nitrate solution to produce a precipitation solution from which catalyst precursor precipitates, wherein the ratio of ferrous nitrate solution to ferric nitrate solution in the precipitation solution is a desired ratio;

(b) co-feeding a ferric nitrate solution and a precipitation agent into a ferrous nitrate solution to produce a precipitation solution from which catalyst precursor precipitates, wherein the ratio of ferrous nitrate solution to ferric nitrate solution in the precipitation solution is a desired ratio; or

(c) precipitating a ferrous precipitate from a ferrous nitrate solution by contacting the ferrous nitrate solution with a first precipitation agent; precipitating a ferric precipitate from ferric nitrate solution by contacting the ferric nitrate solution with a second precipitation agent; and combining the ferrous precipitate and the ferric precipitate to form the catalyst precursor, wherein the ratio of ferrous precipitate to ferric precipitate is a desired ratio;

wherein the iron phases are chosen from iron carbonates, iron oxides, iron hydroxides or combinations thereof.

2 . The method of claim 1 wherein the precipitation agent is selected from the group consisting of NH 4 OH, (NH 4 ) 2 CO 3 , NH 4 HCO 3 , NaOH, Na 2 CO 3 , NaHCO 3 , KOH, K 2 CO 3 , KHCO 3 , and combinations thereof.

3 . The method of claim 2 wherein the precipitation agent comprises sodium carbonate.

4 . The method of claim 2 wherein the precipitation agent comprises ammonium hydroxide.

5 . The method of claim 1 wherein the first precipitation agent and the second precipitation agent are the same.

6 . The method of claim 1 wherein the ratio of ferrous nitrate solution to ferric nitrate solution is in the range of from about 1:2.3 to about 1:10.

7 . The method of claim 6 wherein the ratio of ferrous nitrate solution to ferric nitrate solution is about 1:3.

8 . The method of claim 6 wherein the ratio of ferrous nitrate solution to ferric nitrate solution is about 1:9.

10 . The method of claim 1 further comprising co-precipitating at least one other metal or metalloid from a nitrate solution.

11 . The method of claim 10 wherein the at least one other metal or metalloid is selected from the group consisting of magnesium, copper, aluminum, silicon, and combinations thereof.

12 . The method of claim 1 wherein the ferrous nitrate solution, the ferric nitrate solution, the precipitation solution, or a combination thereof comprises at least one other metal or metalloid.

13 . The method of claim 1 wherein (c) further comprises precipitating at least one other precipitate from an additional nitrate solution with a precipitation agent, and wherein combining the ferrous precipitate and the ferric precipitate to form the catalyst precursor further comprises combining the at least one other precipitate with the ferrous precipitate and the ferric precipitate.

14 . The method of claim 13 wherein the additional nitrate solution comprises a metal or metalloid selected from the group consisting of aluminum, silicon, magnesium, copper, and combinations thereof.

15 . The method of claim 14 wherein the additional nitrate solution comprises copper.

16 . A catalyst precursor according to claim 1 .

17 . A method of producing a catalyst, the method comprising:

obtaining a catalyst precursor according to claim 1 ;

washing the catalyst precursor; and

alkalizing the washed catalyst precursor with an alkaline material.

18 . The method of claim 17 wherein the alkaline material comprises potassium carbonate.

19 . The method of claim 17 wherein the desired ratio of ferrous nitrate solution to ferric nitrate solution is in the range of from about 1:2.3 to about 1:10.

20 . The method of claim 19 wherein the ratio of ferrous nitrate solution to ferric nitrate solution is about 1:3.

21 . The method of claim 19 wherein the ratio of ferrous nitrate solution to ferric nitrate solution is about 1:9.

22 . The method of claim 17 further comprising co-precipitating at least one other metal or metalloid from a nitrate solution.

23 . The method of claim 22 wherein the at least one other metal or metalloid is selected from the group consisting of magnesium, copper, aluminum, silicon, and combinations thereof.

24 . The method of claim 22 wherein the ferrous nitrate solution, the ferric nitrate solution, the precipitation solution, or a combination thereof comprises at least one other metal or metalloid.

25 . The method of claim 17 wherein (c) further comprises precipitating at least one other precipitate from an additional nitrate solution with a precipitation agent, and wherein combining the ferrous precipitate and the ferric precipitate to form the catalyst precursor further comprises combining the at least one other precipitate with the ferrous precipitate and the ferric precipitate.

26 . The method of claim 25 wherein the additional nitrate solution comprises a metal or metalloid selected from the group consisting of aluminum, silicon, magnesium, copper, and combinations thereof.

27 . The method of claim 17 further comprising contacting the washed catalyst precursor with a structural promoter to produce a promoted the catalyst.

28 . A catalyst according to claim 17 .

29 . The catalyst of claim 28 wherein the desired ratio of ferrous nitrate solution to ferric nitrate solution is in the range of from about 1:2.3 to about of about 1:10.

30 . The method of claim 29 wherein the ratio of ferrous nitrate solution to ferric nitrate solution is about 1:3.